For someone who regards technological gizmos such as HawkEye the way a Ukipper might view an immigration advice centre financed by the European Development Fund, it has been a landmark few days for Roger Federer. On Thursday he joined Twitter. On Friday he did an "Ask Me Anything" Q&A on reddit. At this rate, a self-published Goats That Look Like Roger Federer Tumblr is just days away.

But while there was froth on his Twitter feed ("Two bandanas to choose from for my 1st match tmrw: I'll let YOU decide between 1. White 2. Violet. Reply with the #!") and fawning in his reddit session ("Q. How do you keep your hair so perfect? A. I really don't. I fight it every day like everybody else"), Federer was revealing too. Particularly when he was asked: "If you had an upcoming match against a 2007 Roger Federer, what would your strategy be to win and how do you think you would fare?"

That was the era when Federer's racket still played like a Stradivarius, and it didn't feel outlandish for the American writer David Foster Wallace to compare watching him to a religious experience. It was Wallace, too, who accurately described those "Federer Moments" – the "times, as you watch the young Swiss play, when the jaw drops and eyes protrude and sounds are made that bring spouses in from other rooms to see if you're OK".

In 2007 Federer made all four grand slam finals, winning three. And while he wasn't quite as dominant as in 2006 – when he won 92 matches and lost only five, arguably the greatest year from any player in the open era – he was still riding the wave that brought him an astonishing 12 of his 17 grand slams between 2004 and 2007.

Back then, only red dirt and Rafael Nadal could halt him, but briefly; like someone in a high-performance sports car who hits a spot of traffic while going 160mph on the autobahn. As one reddit poster put it: "You either had to be Jesus or Nadal on clay to beat 2007 Federer."

Which brings us to Federer's answer. "Well first, I hope I'm a better player today than I was back then," he typed. "I feel like I'm a more complete player today. Although my game hasn't changed much, my experience would allow me fewer mistakes and the ability to deal with challenges a little bit easier."

A more complete player? Fewer mistakes? Those who watched Federer, who returned from a two-month break in March and April with shorter hair and a kangaroo pouch, being pulverised 6-1, 6-3 by Nadal in Rome last weekend will be spluttering into their morning cappuccinos. In the first set, in particular, his forehand resembled a garden sprayer set to random.

But Federer's response can be taken a couple of ways: either he's serious – which is some compliment to Nadal and Novak Djokovic – or, more likely, that he is not so much raging against the dying of the light as ignoring it altogether.

In doing so he would hardly be alone. Athletes, particularly the great ones, can be remarkablly delusional: their internal monologue convincing them of one thing while the evidence screams another.

But that evidence is stacking up. Federer has won only four grand slams since the start of 2008 which, even given the exceptional state of men's tennis in the past half-decade, is worth acknowledging. More pertinently, his win/loss record this season is a middling 18-6, and he arrived in Paris without having won a title in the calendar year – the first time since 2000 – and with defeats by Tomas Berdych, Kei Nishikori and Julien Benneteau on his ledger.

There have been questions – increasingly – about retirement. Concerns too about a niggly back injury, even though Federer's serve stings like it ever did. Toni Nadal, Rafa's coach, dismissed Federer's chances in Paris, saying: "I do not see him among the favourites … maybe at Wimbledon or the US Open, but not at Roland Garros." He was far from alone.

And yet, and yet. The draw gods have been kind, keeping Federer away from Nadal and Djokovic until the final, and easing him into the tournament with matches against two qualifiers – the first of which, the 21-year-old Spaniard Pablo Carreño, was dismissed with the loss of just seven games on Sunday afternoon.

A brigade of Frenchman lie in wait: Benneteau in the third round, Gilles Simon in the last 16 and Jo-Wilfried Tsonga – who has been crushed by Federer in their two matches on clay – in the quarters. And then, possibly, David Ferrer, against whom he holds a 14-0 record, in the last four. There have been more hazardous journeys to a grand slam final.

Of course Nadal – whom Federer has not beaten on clay since 2009 -would be an overwhelming favourite should he survive that far. And so would Djokovic, even though the pair have split their six games on clay. But while Federer's skills are gently dimming as he approaches his 32nd birthday, it would not be such a shock to see him in a Paris final again. The bookies make him third favourite. That seems about right.